I hear a high pitched whistling noise coming from my front left tire and under my truck. I have a 05 Silverado 2500HD. It does it both driving and idling. What could it be?

Answer

It could be a vacuum leak of some sort. You'll need to pinpoint the location of the noise and see if you have any disconnected or broken vacuum lines.

Updated on March 29, 2018

Original Article:

Four Common Car Noises
By Eddie Carrara
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